Harmonic slide rule



P 1942- D. A. MAFFEI HARMONIC SLIDE RULE Filed Feb. 19, 1941.

2 Sheets-Sheet l INVENTOR DOMINICA A. Mfifi/ ATTORNEY April 21, 1942.

D. A. MAFFEI HARMONIC SLIDE RULE Filed Feb. 19, 1941 2 Sheets-Sheet 2INVENTOR D NICK 19. MAI-"FE! ATTORNEY Patented Apr. 21, 1942 UNITEDSTATES PATENT OFFICE HARMONIC SLIDE RULE Dominick A. Mafiei, Bayside,Long Island, N. Y.

Application February 19, 1941, Serial No. 379,606

11 Claims. (01. 84480) This invention relates to harmonic slide rules;and more particularly to devices adapted to effect a ready determinationof the constituent notes of certain selected musical chords.

It frequently becomes necessary, both for the beginner in music as wellas the experienced musician, to determine the notes constituting anygiven chord for any selected key. In the case of the beginner, it isgenerally extremely diflicult to ascertain the tone intervals in variouschords; and unless a person has had some harmonic training, it is attimes practically impossible to figure out the constituent parts ofcertain chords that are known only by technical terminology. Even theexperienced musician may not be familiar with every chord combination,such as those employed, for example, in modern music although he mayhave a thorough schooling in fundamental harmony. It is hence primarilywithin the contemplation of this invention to facilitate the readydetermination of the constituent notes of any musical chord, andparticularly to enable the simultaneous ascertainment of the componentparts of a number of preselected chords.

In the above aspect of my invention, it is a further object to enable,by a simple manual manipulation, the ready determination of theconstituent parts of any selected chord or chords in any key whatsoever.

. It is another object of my invention to enable the constituentelements of selected chords to be readily ascertained not only by nameor symbol, but also with respect to their relative positions on a piano.And in this aspect of my invention it is a further object to enable thestructural embodiment thereof to be cooperatively employed with thekeyboard of a piano whereby the precise positions of the notesconstituting any selected chord will be readily indicated, and wherebythe constituent notes thereof may be readily played upon the piano.

Another object of my invention is to enable a selected series of chordcombinations to be interchangeably displayed and adapted for manualmanipulation. In this manner when a sequence of chords is known orgiven, such as appears in almost every piece of popular music, the slideelements of my device can be arranged in such manner that the variouschords will appear in the proper sequence, whereby they may be played inthe order in which they appear in the music. And in this aspect of myinvention, it is another object to enable the aforesaid sequence ofchords to be shifted almost instantly to any key, so that the music maybe played in a new key with all the chord notes properly indicated.

Another object of this invention is to enable it to be readily used notonly by instrumentalists but also by vocalists and choruses whereharmonic combinations must be carefully planned, and at times instantlyvaried.

It is commonly known amongst musicians that in certain chords there maybe one or two notes that have special musical value or significance andwhich are sometimes characterized as feature notes. With a knowledge ofwhat such special feature notes are for various chords, instrumentalistsfrequently are enabled to improvise musical phrases or sequences aroundsuch tones as a, nucleus. It is hence another object of this inventionto enable such feature notes to be indicated along with the otherconstituent parts of the chord.

Other objects, features and advantages will appear from the drawings andthe description hereinafter given.

Referring to the drawings,

Figure 1 is a front perspective view of my invention shown inconjunction with the keyboard of a piano.

Figure 2 is a fragmentary section of Figure 1 taken substantially alongline 2--2.

Figure 3 is an enlarged fragmentary perspective of a slide member usedwith my invention.

Figure 4 is a front view of a modified form of my invention employingtubular slides.

Figure 5 is an enlarged section of Figure 4 taken along line 55, and

Figure 6 is an enlarged fragmentary perspective of one of the slideelements employed in the form of my invention illustrated in Figures 4and 5.

Referring to the form of my invention shown in Figures 1, 2 and 3 of thedrawings, a fiat backboard or slide support I0 is employed adapted forplacement upon the keyboard ll of a piano, preferably behind the blackkeys thereof. The said support if! has marked thereon a series of blackand white stripes l2 and I3, respectively, these stripes beingpreferably of equal width and being disposed vertically and spaced tocorrespond with the spacing of the black and white keys of the keyboard.In other words, when properly placed upon the keyboard of a piano, theblack and white spaces of the support will correspond and be inlongitudinal registry with the black and white keys of the piano,respectively. It is preferred that each space be lettered to correspondwith the piano keys, at some suitable portion thereof. In the particulardesign illustrated, there are upper lines of notations 4 extendinglengthwise of the support and giving the names of the keys in sharps andflats; and at the bottom of the board there is another line N5 ofnotations giving the notations only of the white keys. There are also,in the preferred form of my invention, two staffs l6 and. I! with notesthereon, corresponding to the keys represented by the black and whitespaces in which such notes appear. The said notations hence represent achromatic sequence of notes, and should extend over a span of at leastone octave.

The said board It is provided with slide retainers is adapted toslidably and visibly accommodate the slide members [9 therein. In theform of my invention illustrated the said retainers are secured inspaced relation on the support by the eyelets 2il--it being understood,however, that other suitable securing means may be employed. It is alsopreferred that the retainers I8 be arranged to slidably accommodate aplurality of parallel horizontally disposed slides IS in such mannerthat there be enlarged spaces 2! between groups of said slides. InFigure l the groupings are shown each to consist of three slides. Theslides are movable along paths in the general direction of the extent ofthe said notations, parallel to lines l4 and I5, and transversely acrossthe stripes l2 and I3.

Each of the slides It contains at an extreme terminal portion a chordinsignia 22 indicating the technical designation of the chord. The slidealso contains, in proper spaced relation with respect to the spaces [2and I3 and the corresponding keys on the piano, note-indicating markings23 and 24 to designate the particular position of the constituent notesof the desig- L nated chord. In the form of my invention illustratedthese markings are in the form of apertures punched into the body of theslide. Certain of these markings or apertures are square, as designatedby the reference numerals 23, and certain others are round as designatedby the reference numerals 24, The round ones designate theabove-referred-to feature notes, whereas the others represent the rootor other constituent notes of the chord. Apertured markings 23 and 2:1are preferred over other types of markings such as printed notations andthe like, inasmuch as they can be more readily distinguished and read byblind performers. Each one of the said markings may also, if it is sodesired, contain symbols adjacent thereto to indicate the particularinterval designation of the corresponding note in the given key,

The said slides 19 are selected in accordance with the chord insignia 22thereon, the entire apparatus being supplied with slides to correspondwith any and every type of chord that may be deemed necessary. If it isdesired to determine the constituent parts of the chord represented by aselected slide, the extreme left or key-setting marking aperture 23a isplaced on a space corresponding with the desired key. For example, byreferring to Figure l, the upper most slide 19, designating a majorchord by virtue of the notation MA. at the left extremity thereof, isshown with the key-setting marking 23a over the extreme left spacedesignated F. The markings 23 and 24 will hence indicate the constituentnotes of the major chord in the key of F, such notes being F, A, C, F,etc. Should a person desire to play a chord, all. that he needs to do isto follow the spaces l2 or it, as indicated by said markings, down tothe keyboard, and strike the corresponding keys. Should it be desired toget the major chord for another key, such as G sharp, the said marking23a is placed over the black space marked G sharp, and the otherconstituent parts of the chord in that key will be found in like manner.

Where a sequence of chords must be played as indicated by a sheet ofmusic and where chord changes are shown by suitable conventionalnotations, a plurality of slides 19 are placed within the retainers E8in the order in which they appear on the sheet music. The slidesselected must conform with the chords indicated on the sheet music, andthe position of each of said slides must be set in accordance with saidconventional musical notations. With such a setting, all that need bedone during a reading of the music is to play the chords in sequence asindicated progressively by the slides, beginning with the top slide andcontinuing down towards the last one. As each successive notation on thesheet music is reached, the chord indicated by the corresponding slideis playedthe precise position on the keyboard of each note in such chordbeing indicated by the prolongation of the spaces [2 and lit in themanner above described. To facilitate the use of such slides,particularly where a plurality of them are employed, the groupings abovereferred to are resorted to, the spaces 2| between groups being providedfor this purpose.

By the method above described, a beginner can easily learn the locationand constituent elements of various chords, and also may be able toaccompany a singer or an instrumentalist by playing the chords inaccordance with the setting of the slides. An experienced musician canexperiment with various combinations of slides to determine or createmusical effects, and can also employ the markings 2G to determine thesocalled feature notes for whatever purpose he may find it expedient touse them.

In the form of my invention illustrated in Figures 4, 5 and 6, insteadof flat slides I9, I employ a plurality of cylindrical slides 25 eachcontaining on the surface thereof a plurality of longitudinally arrangedgroups of markings, each group consisting of a series of markings spacedto correspond with the particular chord designating symbol adjacentthereto. For example, there is the group of markings longitudinallydisposed along level 26 representing, for example, a major chordand thenthere is another parallel and longitudinally disposed group of markingsarranged along level 2! representing a minor chord. And so eachcylindrical slide 25 may contain on the outer surface thereof aplurality of groups of markings representing a corresponding pluralityof chords. Although the slides illustrated are solid, they may obviouslybe hollow or of any other cylindrical form permitting the cylindricalsurface thereof to contain the markings hereinabove referred to.

A selected number of such slides 25 are adapted to be slidably androtatively held by the support 28 which, in the form illustrated,consists of a front panel 29 and a rear panel 30 separated by Walls 3!to form compartments 32 for the said slides. The front panel 29 containsa plurality of horizontally disposed windows or apertures 33 tocorrespond with each of said compartments and through which a line ofthe markings 34 on said slide 25 may be visible. It is preferred thatthe front panel 29 be shorter than rear panel 30 so that the terminaledge 35 of said front panel may be sufficiently above the keyboard toclear the black notes.

In the operation of this form of my invention, a selection is made ofone or more slides 25 in accordance with the desired chords. Then bymanipulating each slide rotatively, it is apparent that difierent rows26, 21, etc., of markings will be successively visible through thewindows 33. Inasmuch as each row represents a different chord, thecomponent parts of each chord can be quickly determined by suitablerotative manipulation of the slide until the desired row is visible, andnoting the position of the markings with respect to the stripes 36 and31, or key notations, in the manner aforesaid. Should it be desired todetermine the constituent parts of a designated chord for any other key,all that need be done is to slide said slide longitudinally until theextreme left key-setting marking is disposed over the black or whitestripes 36 or 3! corresponding with the desired key, and observationsmade accordingly. It is apparent that with this arrangement there willbe less frequent occasion to change the slides, inasmuch as there are anumber of different chord arrangements on each slide.

Both forms of my invention above described, and the various adaptationsthereof, are effective not only in indicating the constituent notes of agiven chord, but are useful also in visibly indicating the relationshipof a successive series of notes constituting part of a given melody,with respect to a chord that may be musically associated with suchnotes, even if the notes of said series do not constitute componentparts of the said chord. For example, if a slide for a given chord isproperly set on the support 10, a series of subsequent melody slides maybe positioned below said chord slide to indicate, in succession, theindividual melody notes which may be played with the said given chord.It is preferred that the extreme left marking 23a of each so-calledmelody slide be employed to indicate the said melody notes to beassociated with the said given chord.

Although the drawings indicate slide supports containing stripesarranged for registry with the keys of a piano, it is understood thatthe stripes or analogous markings may be arranged for registry with keyor note positions on other instruments, in accordance with the physicalcharacteristics of the instrument, such as the fingerboard of a violin.It is to be further understood that although the slides above describedare illustrated as being horizontally positioned, they may of course bemovably arranged along di:ffer ently disposed paths, and that numerousother changes and modifications, besides those hereinabove described,may be made within the scope of the appended claims without departingfrom the spirit of this invention.

What I claim is:

1. In a harmonic slide rule of the class described, a support havingthereon a plurality of spaced notations representing a chromaticsequence of notes over a span of at least one octave, and a slide memberin slidabl engagement with said support and movable along a pathextending in the general direction of said notations, said member havingthereon a chord insignia representing the designation of a predeterminedchord, and a plurality of markings spaced for cooperative registry withsaid spaced notations in accordance with and limited only to the toneintervals of said chord, said markings being disposed along a lineparallel to said path, substantially the entire extent of said memberalong said line being unobstructed and exposed to view.

2. In a harmonic slide rule of the class described, a support containinga plurality of spaced notations representing a chromatic sequence ofnotes over a span of at least one octave and a plurality ofsubstantially vertical stripes corresponding to and associated with saidnotations, and a slide member in slidable engagement with said supportand movable transversely across said stripes along a predetermined path,said member having thereon a chord insignia representing the designationof a predetermined chord, a key-setting marking corresponding to thefundamental note of a selected key, and a plurality of note-indicatingmarkings spaced from said key-setting marking and from each other inaccordance with the tone intervals of said chord, all said markingsbeing spaced for cooperative registry with said stripes, said markingsbeing disposed along a line parallel to said path, substantially theentire extent of said member along said line being unobstructed andexposed to view.

3. In a harmonic slide rule of the class described, a flat supporthaving thereon a plurality of spaced notations representing a chromaticsequence of notes over a span of at least one octave, and a plurality ofsubstantially parallel slide members in detachable slidable engagementwith said support and each movable along a path extending in the generaldirection of the extent of said rotations, each of said members havingthereon a chord insignia representing the designation of a predeterminedchord, and a plurality of markings spaced for cooperative registry withsaid spaced notations in accordance with and limited only to the toneintervals of said chord, the markings on each member being disposedalong a line parallel to its path, substantially the entire extent ofeach of said members along said line being unobstructed and exposed toview.

4. In a harmonic slide rule of the class described, a support containinga plurality of spaced notations representing a chromatic sequence ofnotes over a span of at least one octave and a plurality ofsubstantially vertical stripes corresponding to and associated with saidnotations, and a slide member in slidable engagement with said supportand movable transversely across said stripes, said member having thereona chord insignia representing the designation of a predetermined chord,and a plurality of apertured markings spaced for cooperative registrywith said stripes in accordance with and limited only to the toneintervals of said chord, said apertured markings being each ofpredetermined configuration to indicate certain harmonic values of thenotes corresponding with the stripes with which said respective markingsare in. registry, said markings being disposed along a line parallel tosaid path, substantially the entire extent of said member along saidline being unobstructed and exposed to view.

5. In combination with the keyboard of a piano, a harmonic slide rulecomprising a support adapted to rest upon said keyboard, said supportcontaining a plurality of spaced notations representing a chromaticsequence of notes over a span of at least one octave and a plurality ofsubstantially vertical stripes corresponding to and associated with saidnotations and in longitudinal registry with the keys of the piano, and aslide member in slidable engagement with said support and movabletransversely across said stripes along a predetermined path, said memberhaving thereon a chord insignia representing the designation of apredetermined chord, and a plurality of markings spaced for cooperativeregistry with said stripes in accordance with and limited only to thetone intervals of said chord, said markings being disposed along a lineparallel to said path, substantially the entire extent of said memberalong said line being unobstructed and exposed to view.

6. In combination with the keyboard of a piano, a harmonic slide rulecomprising a support adapted to rest upon said keyboard, said supportcontaining a plurality of spaced notations representing a chromaticsequence of notes over a span of at least one octave and a plurality ofsubstantially vertical equally spaced stripes corresponding to andassociated with said notations and in longitudinal registry with thekeys of the piano, a slide member movable transversely across the saidstripes of the support along a predetermined path, retaining means onsaid support slidably and visibly supporting said slide member, saidmember having thereon a chord insignia representing the designation of apredetermined chord, and a plurality of markings spaced for cooperativeregistry with said stripes in accordance with and limited only to thetone intervals of said chord, said markings being disposed along a lineparallel to said path, substantially the entire extent of said memberalong said line being unobstructed and exposed to view.

'7. In combination with the keyboard of a piano, a harmonic slide rulecomprising a support adapted to rest upon said keyboard, said supportcontaining a plurality of spaced notations representing a chromaticsequence of notes over a span of at least one octave and a plurality ofsubstantially vertical stripes corresponding to and associated with saidnotations and in longitudinal registry with the keys of the piano, and aplurality of substantially parallel slide members in slidable engagementwith said support and each movable transversely across the said stripesalong a predetermined path, said slide members being arranged in spacedgroups each containing a predetermined number of members, each of saidmembers having thereon a chord insignia representing the designation ofa predetermined chord, and a plurality of markings spaced forcooperative registry with said stripes in accordance with and limitedonly to the tone intervals of said chord, the markings on each memberbeing disposed along a line parallel to its path, substantially theentire extent of each of said members along said line being unobstructedand exposed to view.

8. In a harmonic slide rule of the class de scribed, a support havingthereon a plurality of spaced notations representing a chromaticsequence of notes over a span of at least one octave, and a cylindricalslide member in slidable engagement with said support and movable alonga path extending in the general direction of said notations, said memberhaving on the outer sur face thereof a plurality of chord insignia eachrepresenting the designation of a predetermined chord, and a group ofmarkings for each of said insignia, the markings for each group beingspaced for cooperative registry with said spaced notations in accordancewith the tone intervals of the chord corresponding to the insigniaassociated with the particular group.

9. In a harmonic slide rule of the class described, a support havingthereon a plurality of spaced notations representing a chromaticsequence of notes over a span of at least one octave, and a cylindricalslide in slidable and rotatable engagement with said support, saidmember being movable along a path extending in the general direction ofsaid notations, said member having on the outer surface thereof aplurality of chord insignia each representing the designation of apredetermined chord, and a group of markings for each of said insignia,the markings for each group being disposed along a line longitudinallyof the cylinder and being spaced for cooperative registry with saidspaced notations in accordance with the tone intervals of the chordcorresponding to the insignia associated with the particular group.

10. In a harmonic slide rule of the class described, a support havingthereon a plurality of spaced notations representing a chromaticsequence of notes over a span of at least one octave, a Window in saidsupport extending over the span of said notations, a cylindrical slidemember behind said window, and means to slidably and rotatably supportsaid member, said member being rotatable about its axis and movablealong a path extending in the general direction of said notations, saidmember having on the outer surface thereof a plurality of chord insigniaeach representing the designation of a predetermined chord, and a groupof markings for each of said insignia, the markings for each group beingspaced for cooperative registry with said spaced notations in accordancewith the tone intervals of the chord corresponding to the insigniaassociated with the particular group, the said groups of markings beingmovable successively into registry with and visible through said windowupon an operative rotation of the said member.

11. In combination with the keyboard of a piano, a harmonic slide rulecomprising a support adapted to rest upon said keyboard, said supportcontaining longitudinally thereof a plurality of spaced notationsrepresenting a chromatic sequence of notes over a span of at least oneoctave and a plurality of substantially vertical stripes correspondingto and associated with said notations and in longitudinal registry withthe keys of the piano, a plurality of parallel windows in said supporteach extending transversely across said stripes, a plurality of parallelwindows in said support each extending transversely across said stripes,a plurality of parallel cylindrical slide members each disposed behindone of said windows, and means to slidably and rotatably support each ofsaid members, each of said members being rotatable about its axis andmovable transversely across said stripes, each of the members having onthe outer surface thereof a plurality of chord insignia eachrepresenting the designation of a predetermined chord, and a group ofmarkings for each of said insignia, the markings for each group beingdisposed along a line longitudinally of the cylinder and being spacedfor cooperative registry with said spaced notations in accordance withthe tone intervals of the chord corresponding to the insignia associatedwith the particular group, each group of markings being adapted forregistry with the adjacent window upon an operative manipulation of thecorresponding member.

DOMINICK A. MAFFEI.

